drivers/remoteproc/remoteproc_debugfs.c

   1 // SPDX-License-Identifier: GPL-2.0-only
   2 /*
   3  * Remote Processor Framework
   4  *
   5  * Copyright (C) 2011 Texas Instruments, Inc.
   6  * Copyright (C) 2011 Google, Inc.
   7  *
   8  * Ohad Ben-Cohen <ohad@wizery.com>
   9  * Mark Grosen <mgrosen@ti.com>
  10  * Brian Swetland <swetland@google.com>
  11  * Fernando Guzman Lugo <fernando.lugo@ti.com>
  12  * Suman Anna <s-anna@ti.com>
  13  * Robert Tivy <rtivy@ti.com>
  14  * Armando Uribe De Leon <x0095078@ti.com>
  15  */
  16
  17 #define pr_fmt(fmt)    "%s: " fmt, __func__
  18
  19 #include <linux/kernel.h>
  20 #include <linux/debugfs.h>
  21 #include <linux/remoteproc.h>
  22 #include <linux/device.h>
  23 #include <linux/uaccess.h>
  24
  25 #include "remoteproc_internal.h"
  26
  27 /* remoteproc debugfs parent dir */
  28 static struct dentry *rproc_dbg;
  29
  30 /*
  31  * A coredump-configuration-to-string lookup table, for exposing a
  32  * human readable configuration via debugfs. Always keep in sync with
  33  * enum rproc_coredump_mechanism
  34  */
  35 static const char * const rproc_coredump_str[] = {
  36         [RPROC_COREDUMP_DISABLED]       = "disabled",
  37         [RPROC_COREDUMP_ENABLED]        = "enabled",
  38         [RPROC_COREDUMP_INLINE]         = "inline",
  39 };
  40
  41 /* Expose the current coredump configuration via debugfs */
  42 static ssize_t rproc_coredump_read(struct file *filp, char __user *userbuf,
  43                                    size_t count, loff_t *ppos)
  44 {
  45         struct rproc *rproc = filp->private_data;
  46         char buf[20];
  47         int len;
  48
  49         len = scnprintf(buf, sizeof(buf), "%s\n",
  50                         rproc_coredump_str[rproc->dump_conf]);
  51
  52         return simple_read_from_buffer(userbuf, count, ppos, buf, len);
  53 }
  54
  55 /*
  56  * By writing to the 'coredump' debugfs entry, we control the behavior of the
  57  * coredump mechanism dynamically. The default value of this entry is "disabled".
  58  *
  59  * The 'coredump' debugfs entry supports these commands:
  60  *
  61  * disabled:    By default coredump collection is disabled. Recovery will
  62  *              proceed without collecting any dump.
  63  *
  64  * enabled:     When the remoteproc crashes the entire coredump will be copied
  65  *              to a separate buffer and exposed to userspace.
  66  *
  67  * inline:      The coredump will not be copied to a separate buffer and the
  68  *              recovery process will have to wait until data is read by
  69  *              userspace. But this avoid usage of extra memory.
  70  */
  71 static ssize_t rproc_coredump_write(struct file *filp,
  72                                     const char __user *user_buf, size_t count,
  73                                     loff_t *ppos)
  74 {
  75         struct rproc *rproc = filp->private_data;
  76         int ret, err = 0;
  77         char buf[20];
  78
  79         if (count > sizeof(buf))
  80                 return -EINVAL;
  81
  82         ret = copy_from_user(buf, user_buf, count);
  83         if (ret)
  84                 return -EFAULT;
  85
  86         /* remove end of line */
  87         if (buf[count - 1] == '\n')
  88                 buf[count - 1] = '\0';
  89
  90         if (rproc->state == RPROC_CRASHED) {
  91                 dev_err(&rproc->dev, "can't change coredump configuration\n");
  92                 err = -EBUSY;
  93                 goto out;
  94         }
  95
  96         if (!strncmp(buf, "disabled", count)) {
  97                 rproc->dump_conf = RPROC_COREDUMP_DISABLED;
  98         } else if (!strncmp(buf, "enabled", count)) {
  99                 rproc->dump_conf = RPROC_COREDUMP_ENABLED;
 100         } else if (!strncmp(buf, "inline", count)) {
 101                 rproc->dump_conf = RPROC_COREDUMP_INLINE;
 102         } else {
 103                 dev_err(&rproc->dev, "Invalid coredump configuration\n");
 104                 err = -EINVAL;
 105         }
 106 out:
 107         return err ? err : count;
 108 }
 109
 110 static const struct file_operations rproc_coredump_fops = {
 111         .read = rproc_coredump_read,
 112         .write = rproc_coredump_write,
 113         .open = simple_open,
 114         .llseek = generic_file_llseek,
 115 };
 116
 117 /*
 118  * Some remote processors may support dumping trace logs into a shared
 119  * memory buffer. We expose this trace buffer using debugfs, so users
 120  * can easily tell what's going on remotely.
 121  *
 122  * We will most probably improve the rproc tracing facilities later on,
 123  * but this kind of lightweight and simple mechanism is always good to have,
 124  * as it provides very early tracing with little to no dependencies at all.
 125  */
 126 static ssize_t rproc_trace_read(struct file *filp, char __user *userbuf,
 127                                 size_t count, loff_t *ppos)
 128 {
 129         struct rproc_debug_trace *data = filp->private_data;
 130         struct rproc_mem_entry *trace = &data->trace_mem;
 131         void *va;
 132         char buf[100];
 133         int len;
 134
 135         va = rproc_da_to_va(data->rproc, trace->da, trace->len);
 136
 137         if (!va) {
 138                 len = scnprintf(buf, sizeof(buf), "Trace %s not available\n",
 139                                 trace->name);
 140                 va = buf;
 141         } else {
 142                 len = strnlen(va, trace->len);
 143         }
 144
 145         return simple_read_from_buffer(userbuf, count, ppos, va, len);
 146 }
 147
 148 static const struct file_operations trace_rproc_ops = {
 149         .read = rproc_trace_read,
 150         .open = simple_open,
 151         .llseek = generic_file_llseek,
 152 };
 153
 154 /* expose the name of the remote processor via debugfs */
 155 static ssize_t rproc_name_read(struct file *filp, char __user *userbuf,
 156                                size_t count, loff_t *ppos)
 157 {
 158         struct rproc *rproc = filp->private_data;
 159         /* need room for the name, a newline and a terminating null */
 160         char buf[100];
 161         int i;
 162
 163         i = scnprintf(buf, sizeof(buf), "%.98s\n", rproc->name);
 164
 165         return simple_read_from_buffer(userbuf, count, ppos, buf, i);
 166 }
 167
 168 static const struct file_operations rproc_name_ops = {
 169         .read = rproc_name_read,
 170         .open = simple_open,
 171         .llseek = generic_file_llseek,
 172 };
 173
 174 /* expose recovery flag via debugfs */
 175 static ssize_t rproc_recovery_read(struct file *filp, char __user *userbuf,
 176                                    size_t count, loff_t *ppos)
 177 {
 178         struct rproc *rproc = filp->private_data;
 179         char *buf = rproc->recovery_disabled ? "disabled\n" : "enabled\n";
 180
 181         return simple_read_from_buffer(userbuf, count, ppos, buf, strlen(buf));
 182 }
 183
 184 /*
 185  * By writing to the 'recovery' debugfs entry, we control the behavior of the
 186  * recovery mechanism dynamically. The default value of this entry is "enabled".
 187  *
 188  * The 'recovery' debugfs entry supports these commands:
 189  *
 190  * enabled:     When enabled, the remote processor will be automatically
 191  *              recovered whenever it crashes. Moreover, if the remote
 192  *              processor crashes while recovery is disabled, it will
 193  *              be automatically recovered too as soon as recovery is enabled.
 194  *
 195  * disabled:    When disabled, a remote processor will remain in a crashed
 196  *              state if it crashes. This is useful for debugging purposes;
 197  *              without it, debugging a crash is substantially harder.
 198  *
 199  * recover:     This function will trigger an immediate recovery if the
 200  *              remote processor is in a crashed state, without changing
 201  *              or checking the recovery state (enabled/disabled).
 202  *              This is useful during debugging sessions, when one expects
 203  *              additional crashes to happen after enabling recovery. In this
 204  *              case, enabling recovery will make it hard to debug subsequent
 205  *              crashes, so it's recommended to keep recovery disabled, and
 206  *              instead use the "recover" command as needed.
 207  */
 208 static ssize_t
 209 rproc_recovery_write(struct file *filp, const char __user *user_buf,
 210                      size_t count, loff_t *ppos)
 211 {
 212         struct rproc *rproc = filp->private_data;
 213         char buf[10];
 214         int ret;
 215
 216         if (count < 1 || count > sizeof(buf))
 217                 return -EINVAL;
 218
 219         ret = copy_from_user(buf, user_buf, count);
 220         if (ret)
 221                 return -EFAULT;
 222
 223         /* remove end of line */
 224         if (buf[count - 1] == '\n')
 225                 buf[count - 1] = '\0';
 226
 227         if (!strncmp(buf, "enabled", count)) {
 228                 /* change the flag and begin the recovery process if needed */
 229                 rproc->recovery_disabled = false;
 230                 rproc_trigger_recovery(rproc);
 231         } else if (!strncmp(buf, "disabled", count)) {
 232                 rproc->recovery_disabled = true;
 233         } else if (!strncmp(buf, "recover", count)) {
 234                 /* begin the recovery process without changing the flag */
 235                 rproc_trigger_recovery(rproc);
 236         } else {
 237                 return -EINVAL;
 238         }
 239
 240         return count;
 241 }
 242
 243 static const struct file_operations rproc_recovery_ops = {
 244         .read = rproc_recovery_read,
 245         .write = rproc_recovery_write,
 246         .open = simple_open,
 247         .llseek = generic_file_llseek,
 248 };
 249
 250 /* expose the crash trigger via debugfs */
 251 static ssize_t
 252 rproc_crash_write(struct file *filp, const char __user *user_buf,
 253                   size_t count, loff_t *ppos)
 254 {
 255         struct rproc *rproc = filp->private_data;
 256         unsigned int type;
 257         int ret;
 258
 259         ret = kstrtouint_from_user(user_buf, count, 0, &type);
 260         if (ret < 0)
 261                 return ret;
 262
 263         rproc_report_crash(rproc, type);
 264
 265         return count;
 266 }
 267
 268 static const struct file_operations rproc_crash_ops = {
 269         .write = rproc_crash_write,
 270         .open = simple_open,
 271         .llseek = generic_file_llseek,
 272 };
 273
 274 /* Expose resource table content via debugfs */
 275 static int rproc_rsc_table_show(struct seq_file *seq, void *p)
 276 {
 277         static const char * const types[] = {"carveout", "devmem", "trace", "vdev"};
 278         struct rproc *rproc = seq->private;
 279         struct resource_table *table = rproc->table_ptr;
 280         struct fw_rsc_carveout *c;
 281         struct fw_rsc_devmem *d;
 282         struct fw_rsc_trace *t;
 283         struct fw_rsc_vdev *v;
 284         int i, j;
 285
 286         if (!table) {
 287                 seq_puts(seq, "No resource table found\n");
 288                 return 0;
 289         }
 290
 291         for (i = 0; i < table->num; i++) {
 292                 int offset = table->offset[i];
 293                 struct fw_rsc_hdr *hdr = (void *)table + offset;
 294                 void *rsc = (void *)hdr + sizeof(*hdr);
 295
 296                 switch (hdr->type) {
 297                 case RSC_CARVEOUT:
 298                         c = rsc;
 299                         seq_printf(seq, "Entry %d is of type %s\n", i, types[hdr->type]);
 300                         seq_printf(seq, "  Device Address 0x%x\n", c->da);
 301                         seq_printf(seq, "  Physical Address 0x%x\n", c->pa);
 302                         seq_printf(seq, "  Length 0x%x Bytes\n", c->len);
 303                         seq_printf(seq, "  Flags 0x%x\n", c->flags);
 304                         seq_printf(seq, "  Reserved (should be zero) [%d]\n", c->reserved);
 305                         seq_printf(seq, "  Name %s\n\n", c->name);
 306                         break;
 307                 case RSC_DEVMEM:
 308                         d = rsc;
 309                         seq_printf(seq, "Entry %d is of type %s\n", i, types[hdr->type]);
 310                         seq_printf(seq, "  Device Address 0x%x\n", d->da);
 311                         seq_printf(seq, "  Physical Address 0x%x\n", d->pa);
 312                         seq_printf(seq, "  Length 0x%x Bytes\n", d->len);
 313                         seq_printf(seq, "  Flags 0x%x\n", d->flags);
 314                         seq_printf(seq, "  Reserved (should be zero) [%d]\n", d->reserved);
 315                         seq_printf(seq, "  Name %s\n\n", d->name);
 316                         break;
 317                 case RSC_TRACE:
 318                         t = rsc;
 319                         seq_printf(seq, "Entry %d is of type %s\n", i, types[hdr->type]);
 320                         seq_printf(seq, "  Device Address 0x%x\n", t->da);
 321                         seq_printf(seq, "  Length 0x%x Bytes\n", t->len);
 322                         seq_printf(seq, "  Reserved (should be zero) [%d]\n", t->reserved);
 323                         seq_printf(seq, "  Name %s\n\n", t->name);
 324                         break;
 325                 case RSC_VDEV:
 326                         v = rsc;
 327                         seq_printf(seq, "Entry %d is of type %s\n", i, types[hdr->type]);
 328
 329                         seq_printf(seq, "  ID %d\n", v->id);
 330                         seq_printf(seq, "  Notify ID %d\n", v->notifyid);
 331                         seq_printf(seq, "  Device features 0x%x\n", v->dfeatures);
 332                         seq_printf(seq, "  Guest features 0x%x\n", v->gfeatures);
 333                         seq_printf(seq, "  Config length 0x%x\n", v->config_len);
 334                         seq_printf(seq, "  Status 0x%x\n", v->status);
 335                         seq_printf(seq, "  Number of vrings %d\n", v->num_of_vrings);
 336                         seq_printf(seq, "  Reserved (should be zero) [%d][%d]\n\n",
 337                                    v->reserved[0], v->reserved[1]);
 338
 339                         for (j = 0; j < v->num_of_vrings; j++) {
 340                                 seq_printf(seq, "  Vring %d\n", j);
 341                                 seq_printf(seq, "    Device Address 0x%x\n", v->vring[j].da);
 342                                 seq_printf(seq, "    Alignment %d\n", v->vring[j].align);
 343                                 seq_printf(seq, "    Number of buffers %d\n", v->vring[j].num);
 344                                 seq_printf(seq, "    Notify ID %d\n", v->vring[j].notifyid);
 345                                 seq_printf(seq, "    Physical Address 0x%x\n\n",
 346                                            v->vring[j].pa);
 347                         }
 348                         break;
 349                 default:
 350                         seq_printf(seq, "Unknown resource type found: %d [hdr: %pK]\n",
 351                                    hdr->type, hdr);
 352                         break;
 353                 }
 354         }
 355
 356         return 0;
 357 }
 358
 359 DEFINE_SHOW_ATTRIBUTE(rproc_rsc_table);
 360
 361 /* Expose carveout content via debugfs */
 362 static int rproc_carveouts_show(struct seq_file *seq, void *p)
 363 {
 364         struct rproc *rproc = seq->private;
 365         struct rproc_mem_entry *carveout;
 366
 367         list_for_each_entry(carveout, &rproc->carveouts, node) {
 368                 seq_puts(seq, "Carveout memory entry:\n");
 369                 seq_printf(seq, "\tName: %s\n", carveout->name);
 370                 seq_printf(seq, "\tVirtual address: %pK\n", carveout->va);
 371                 seq_printf(seq, "\tDMA address: %pad\n", &carveout->dma);
 372                 seq_printf(seq, "\tDevice address: 0x%x\n", carveout->da);
 373                 seq_printf(seq, "\tLength: 0x%zx Bytes\n\n", carveout->len);
 374         }
 375
 376         return 0;
 377 }
 378
 379 DEFINE_SHOW_ATTRIBUTE(rproc_carveouts);
 380
 381 void rproc_remove_trace_file(struct dentry *tfile)
 382 {
 383         debugfs_remove(tfile);
 384 }
 385
 386 struct dentry *rproc_create_trace_file(const char *name, struct rproc *rproc,
 387                                        struct rproc_debug_trace *trace)
 388 {
 389         struct dentry *tfile;
 390
 391         tfile = debugfs_create_file(name, 0400, rproc->dbg_dir, trace,
 392                                     &trace_rproc_ops);
 393         if (!tfile) {
 394                 dev_err(&rproc->dev, "failed to create debugfs trace entry\n");
 395                 return NULL;
 396         }
 397
 398         return tfile;
 399 }
 400
 401 void rproc_delete_debug_dir(struct rproc *rproc)
 402 {
 403         debugfs_remove_recursive(rproc->dbg_dir);
 404 }
 405
 406 void rproc_create_debug_dir(struct rproc *rproc)
 407 {
 408         struct device *dev = &rproc->dev;
 409
 410         if (!rproc_dbg)
 411                 return;
 412
 413         rproc->dbg_dir = debugfs_create_dir(dev_name(dev), rproc_dbg);
 414         if (!rproc->dbg_dir)
 415                 return;
 416
 417         debugfs_create_file("name", 0400, rproc->dbg_dir,
 418                             rproc, &rproc_name_ops);
 419         debugfs_create_file("recovery", 0600, rproc->dbg_dir,
 420                             rproc, &rproc_recovery_ops);
 421         debugfs_create_file("crash", 0200, rproc->dbg_dir,
 422                             rproc, &rproc_crash_ops);
 423         debugfs_create_file("resource_table", 0400, rproc->dbg_dir,
 424                             rproc, &rproc_rsc_table_fops);
 425         debugfs_create_file("carveout_memories", 0400, rproc->dbg_dir,
 426                             rproc, &rproc_carveouts_fops);
 427         debugfs_create_file("coredump", 0600, rproc->dbg_dir,
 428                             rproc, &rproc_coredump_fops);
 429 }
 430
 431 void __init rproc_init_debugfs(void)
 432 {
 433         if (debugfs_initialized()) {
 434                 rproc_dbg = debugfs_create_dir(KBUILD_MODNAME, NULL);
 435                 if (!rproc_dbg)
 436                         pr_err("can't create debugfs dir\n");
 437         }
 438 }
 439
 440 void __exit rproc_exit_debugfs(void)
 441 {
 442         debugfs_remove(rproc_dbg);
 443 }